School register - ASP.NET project for school management

ASP.NET WEB application. C#, Entity Framework, Dependency Injection, MVC, Razor Pages, unit tests, AutoMapper, AspNetCore.Identity, MS SQL Server

Application Characteristics:
- There are roles: Teacher, Admin, Student, Parent, User
- Admin can edit groups, subjects, attach/detach students to groups.
- Teacher can check students grades and add grades for his students.
- Parent can see his children grades.
Here is a presentation of Admin, Teacher and Parent functionalities:

The application uses MS SQL Server database. The database is created with Entity Framework Code First approach. The application uses Dependency Injection to inject services. The application uses AutoMapper to map database entities to view-models for representation in Razor Pages. The application uses AspNetCore.Identity to manage users and roles. Also there is an implementation of unit tests to test services.
There are several screenshots of code below.
Project structure:
EF Fluent API:
AutoMapper:
IGroupService:
GroupService method example:
Unit test example:

I followed tutorial to create this project. You can download and see the code.